interface USB {
    void work();
    void stop(); 
}

class Mouse implements USB {
    @Override
    public void work() {
        System.out.println("我点点点");
    }

    @Override
    public void stop() {
        System.out.println("我不能点了");
    }
}


class UPan implements USB {
    @Override
    public void work() {
        System.out.println("我存存存");
    }

    @Override
    public void stop() {
        System.out.println("我走了");
    }
}


public class Test40 {
    public static void main(String[] args) {
        
        USB usb1 = new Mouse();
        usb1.work();  
        usb1.stop(); 
        
       
        USB[] usbs = new USB[2];
        usbs[0] = new UPan();
        usbs[1] = new Mouse();
        
        for (USB usb : usbs) {
            usb.work(); 
            usb.stop();  
        }
    }
}